In 2015, the winner is Norway by producing 97.7% of their electricity needs through renewable energy. The top 3 is completed with New Zealand (80.1%) and Columbia (77.7%). The U.S. produces only 13.6% of their electricity with renewable energy. You can learn more from the Global Energy Statistics Yearbook 2017. The data on renewable energy production dates back to 1990. You can download graphs like the one here and the data sets (after registering).